# How to do basic mathematical computations (in R)

See all solutions.

How do we write the most common mathematical operations in a given piece of software? For example, how do we write multiplication, or exponentiation, or logarithms, in Python vs. R vs. Excel, and so on?

## Solution

For those expressions that need the Python math package, use the code import math beforehand to ensure that package is loaded. Alternatively, you can write from math import * and thus drop the math prefixes in the table below.

Mathematical notation R code
$x+y$ x+y
$x-y$ x-y
$xy$ x*y
$\frac xy$ x/y
$x^y$ x^y
$\vert x\vert$ abs(x)
$\ln x$ log(x)
$\log_a b$ log(b,a)
$e^x$ exp(x)
$\pi$ pi
$\sin x$ sin(x)
$\sin^{-1} x$ asin(x)
$\sqrt x$ sqrt(x)

Other trigonometric functions are also available besides just sin, including cos, tan, etc.

R naturally applies these functions across vectors. For example, you can square all the entries in a vector as in the example below.

1
2
example.vector <- c( -3, 2, 0.5, -1, 10, 9.2, -3.3 )
example.vector ^ 2

1
   9.00   4.00   0.25   1.00 100.00  84.64  10.89